Help Find Center Of Gravity of Compound Body

Caption this

For one thing, you show a 2 dimensional object.

The other thing what your really looking for is the Moment of Inertia. Or maybe the Centroid.

Thirdly, you give the density, but not the mass for unit of measurement... of course one could extrapolate...

which way is up, in your diagram? Are these free objects in space, or are we looking down on them as on a plane surface?

How high is each from surface? What do you mean when you say combined? Do you mean in the present positions, but linked, or do you mean all smashed and squished together? Are the objects drawn to the scale indicated in your opening statement?

Is this a normal 4 dimensional universe with space-time curvature?

Good. I think #s 1, 2, & 3 are overthinking it, or maybe (probably??) rabble rousing.

.

Interesting, my numbers are slightly different.

X: 6.7414, Y: 3.7352

hey,... now they're really different...

How you get '.'?

Without indicating the location of the origin, the numbers can be anything. Where is your origin?

ρ = 50:

mass = 8 * 50 = 400

CoM location: 3,4

.

ρ = 100:

mass = 12 * 100 = 1200

CoM location: 4,2

.

ρ = 400:

mass = pi (1.5^2) * 400 = 2827

CoM location: 10,5

.

X_com = (400*3 + 1200*4 + 2827*10) / (400 + 1200 + 2827)

X_com = (1200 + 4800 + 28270) / 4427

X_com = 34270 / 4427

X_com = 7.74

.

Y_com = (400*4 + 1200*2 + 2827*5) / (400 + 1200 + 2827)

Y_com = (1600 + 2400 + 14135) / 4427

Y_com = 18135 / 4427

Y_com = 4.09

.

Aggregate CoM = 7.74, 4.09

4427 pounds.

Check my math. I'm my own worst profreadr

Was that really necessary?

Apparently.

Who's lyn?

Now stop it, just stop it!

Who put Sir Robin off topic.... I put 1 vote on topic...

Sir Robin himself did. He originally posted off-topic. Now he has 5 GAs and nothing to show for it.

Oh,... that happens to me all the time.

Seems a lot of us are in that boat....

Off topic, us? Never, the link is there (arguably tenuous as it may be sometimes).

Speaking of off-topic, anybody know a way to search for the post with the highest off-topic count? Might be kind of amusing to see the "bottom ten".

I don't think the site has that particular feature. I think we have to do it from memory, besides some of the highest have likely been deleted when the whole thread was deleted by the site moderators.

If you are interested try a search on CR4 for post histories of certain particularly <ahem> out of their element and entertaining CR4 users, if I remember correctly those are where the most off-topic flags reside.

Some months I read where one of the mods (or maybe it was Savvy) who, as a joke, marked someone's comment at 10,000 OTs?

Come on, Jack, don't be timid, you can name me, I am almost certain it is me you refer to...hey man, love you one beer.

Really, it didn't even cross my mind. Perhaps you are thinking of political discussion posts, I don't count those (far, far too easy).

I think your answer lies with our new guru, gutmonarch and his predecessors

Once upon a time, a moderator gave somebody 10,000 OT votes (in fun). IIRC, Merph to Doorman.

Hahaha! How did he respond? Like, WTF????

With good humor.

I've employed a "click farm" to bring up my GA count, but it barely keeps me out of the bottom ten.

I think its been hacked.

https://www.recode.net/2017/1/22/14330404/samsung-note-7-problems-battery-investigation-explanation

So that is where all the little cellulars live in the matrix before reality jolts them out in the virtually real world?

Those sounds like two reasonable explanations..

I've read about lithium batteries dimensions a fraction of a mm too large for it's case and essentially 'squishing' them into combustion. (perhaps at some point)

That looks like the "next-gen" massively parallel super computer config.

In danger of getting into murky bath water...
Del

Probably the post I have responded to the most. Just sayin'.

Now, now, he/she never said what they do for a living. For all we know it came up at an accounting firm during the lunch break.

https://www.easycalculation.com/physics/classical-physics/center-of-gravity-calculator.php

Thanks all for the replies and sorry to put you all to so much trouble.

Didn't anyone follow my link to this weeks "caption this". I thought at least Phoenix911 would have recognised the configuration.

I did, but how many times have I told you about copying other peoples work during the exam.

Looking at this picture, shouldn't the (extremely lightweight for a forklift) forklift rectangle be rotated 90° with respect to the torpedo/bomb rectangle?

And what of that round thingo? If that represents the contents of the forklift operator's trousers after dropping that load, shouldn't it be in the driver's seat? Or was he wearing Spandex and landed nearby?

Interesting answer, and clearly a pragmatic means.

This basically how I did it. I changed it to a unitless measurement and used the ratios instead.

These are flat shapes and not bricks, cylinders or spheres, aren't they?

Impossible to solve as stated/shown. Density needs to be in mass/volume. You are showing density as mass/area which makes no sense!

yes, it should have been in lbs/ft³

OR it could be some new 2D universe someone is about to reveal?

I agree that knowing the weight per square foot and (assumption) having gravity facing into the page makes it possible to calculate an answer, but what does that have to do with reality? Don't ask me.

Or he could've simply called it 'pressure' instead. Force/area.

Strictly-speaking, mass isn't a force, and so mass/area isn't a pressure. Weight/area is because it takes into account the acceleration of gravity. Unfortunately the units of mass and of weight have the same names and therein lies the confusion.

That is where carpenters making a world sized room could and would run into problems.

In the limit where gravitation acceleration is not a "local" constant due to a change in effective radius, the weight density over the length of a floor would not be constant, although the mass density would in fact remain constant.

Mathematically, ''lbs/ft²'' is unit-area-weight-density, and ''kg/m²'' is unit-area-mass-density, or if you prefer, weight-density-per-unit-area, and mass-density-per-unit-area, respectively, because:

w = m g (all in appropriately corresponding units)